. >>> the world is on royal baby watch while the mother to be kate middleton is in a long done hospital suffering from extreme morning sickness. her baby is going to be the first royal heir subject to new rules governing succession. >> reporter: of course they have always been crowd pleasers now they are going to be trailblazers their first born will be the first born under the new rules that ensure it will be next in line for the crown, regardless of gender. last year leaders of britain agreed to give females equal status with males in order of succession. for last 100 years if the est child was a girl she would only be queen if none of the younger siblings were boys. now this baby will follow prince william to throne. prince william will follow prince charles. the extreme morning sickness for which kate is in the hospital is commonly associated with twins. if kate is in fact carrying two babies they would be third and fourth in line. >> duty of the wife of the future king is to provide an heir and hopefully, a spare. >> reporter: the current spare is prince harry. kate and william's b